1. Field of the Invention
This invention relates generally to pitchers having a manually operated stirring apparatus, and more particularly relates to such pitchers providing a stirring apparatus which is completely enclosed within the pitcher by a cover and is manually operated by means of a handle that extends through the cover.
2. Background Art
Beverage pitchers having manually operated means for mixing together fluid contents within the pitcher are well known. Recent improvements for such pitchers include covers for the pitchers that provide an essentially fluid tight container, but which nevertheless permit the user to stir up the contents of the container without removing the cover. Examples of such stirring or mixing pitchers are described in U.S. Pat. Nos. 5,695,282, 5,407,270, 5,094,543, 4,893,940, 4,460,279, 4,197,018 and 3,704,007.
Typical problems are encountered in providing a fluid tight cover, including the need for spouts for pouring out the liquid during use. More significantly, a manual stirrer must extend through an aperture, usually extending through the pitcher cover, creating a path of egress from the ambient environment into the pitcher container. Spillage of the fluid within the pitcher resulted. It is also often desired to maintain liquid within the pitcher container cold, and air circulation through an aperture that is not fluid-tight produces undesirable heat transfer which heats up the contained liquid.
The prior art manual mixing mechanisms are often inefficient and/or require substantial manual effort to achieve maximum agitation of the contained liquid and/or entrained solids to achieve total mixing dissolution of the solids within the liquid.